So is my bonus room. Here's what I did. In my case I had the benefit of being on the top floor. I mounted the speakers on the walls up by the ceiling and ran the wires through a hole into the attic, and back down by my cab. The left speaker had no attic access though because that part of the room is an A frame with no attic above. Fortunately that one went right above a window, so I ran the wire down the window behind the blinds, then down to the floor and along the wall by stuffing the wire between the carpet and the baseboard, all the way to the cab. If I hadn't done that, I would have run the wire down the corner where the 2 walls meet, and probably would have painted it to match the wall.
Hope that helps spark some ideas on how you could do the wiring. I was concerned with what my wife would think about how it looks, but it totally passed the wife test and she likes the end result almost as much as I do! Again, it was well worth the effort, so if you can figure out a workable wiring scheme then give it a go.
Heck, if you've got an extra sound card and speakers (or can borrow one from another system) then I suggest starting there and putting the speakers on either side of your cab. That's how I ran mine for a couple of months while I was working on the app, before I bought the stuff to mount the speakers. It was a good way to try it and get an idea of how much I'd like it - but once I finally mounted the speakers it exceeded my expectations!